Officers had tried to stop Calhoun as he drove a 2001 Volvo near 55th and Fairfax avenues in East Oakland. The Volvo was connected to a home-invasion robbery July 12 on the 4700 block of MacArthur Boulevard, during which a resident was pistol-whipped, said Officer Johnna Watson, a police spokeswoman.

Thoms, who has been with the Sheriff's Office for eight years, was named in a lawsuit filed in U.S. District Court filed by Juventino Rodarte, who accused the deputy of unleashing his police dog in March 2013 in San Leandro "without a particularized suspicion that criminal activity was afoot."

The dog "mangled Rodarte's left calf, thereby causing him to lose consciousness," said the suit, which is still pending.

County officials said in court documents that Rodarte was a prowling suspect and that Thoms released his dog because Rodarte appeared to have "some kind of metal object" in his hands. He repeatedly refused to show his hands, authorities said.

After Rodarte was bitten, deputies discovered that the metal object were keys, county officials said.